Authored by Peter Rybin , Chrome DevTools team
In this short guide we'll review some new Chrome DevTools features for "function scope" and "internal properties" by exploring some base JavaScript language concepts.
Let's start with closures – one of the most famous things in JS. A closure is a function, that uses variables from outside. See an example:
Promises are a software abstraction that makes working with asynchronous operations much more pleasant. In the most basic definition, your code will move from continuation-passing style:
getTweetsFor("domenic", function (err, results) {
// the rest of your code goes here.
});
| # These are my notes from the PragProg book on CoffeeScript of things that either | |
| # aren't in the main CS language reference or I didn't pick them up there. I wrote | |
| # them down before I forgot, and put it here for others but mainly as a reference for | |
| # myself. | |
| # assign arguments in constructor to properties of the same name: | |
| class Thingie | |
| constructor: (@name, @url) -> | |
| # is the same as: |
| var application_root = __dirname, | |
| express = require("express"), | |
| path = require("path"), | |
| mongoose = require('mongoose'); | |
| var app = express.createServer(); | |
| // database | |
| mongoose.connect('mongodb://localhost/ecomm_database'); |
| var dateUtil = function () { | |
| var monthDict = ['Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec']; | |
| return { | |
| time: function (date) { | |
| var hour = date.getHours(), | |
| min = date.getMinutes() + "", | |
| ampm = 'AM'; | |
| if (hour == 0) { | |
| hour = 12; |
#Understanding MVC And MVP (For JavaScript & Backbone Developers)
Before exploring any JavaScript frameworks that assist in structuring applications, it can be useful to gain a basic understanding of architectural design patterns. Design patterns are proven solutions to common development problems and can suggest structural paradigms to help guide us in adding some organization to our application.
I think patterns are exciting as they're effectively a grass roots effort that build upon the collective experience of skilled developers who have previously faced similar problems as we do now. Although developers 10 or 20 years ago may not have been using the same programming languages for implementing patterns, there are many lessons we can learn from their efforts.
In this section, we're going to review two popular patterns - MVC and MVP. The context of our exploration will be how these patterns are related to the popular JavaScript framework Backbone.js, which will be explored in greater detail later on.
| Object.extend = function( LeftHandSideExpression, AssignmentExpression ) { | |
| var target, src, needToThrow; | |
| // Let target be ToObject(LeftHandSideExpression). | |
| target = Object( LeftHandSideExpression ); | |
| // Let src be ToObject(AssignmentExpression). | |
| src = Object( AssignmentExpression ); |
| import random | |
| def haiku(): | |
| # originally from: https://gist.github.com/1266756 | |
| # with some changes | |
| # example output: | |
| # "falling-late-violet-forest-d27b3" | |
| adjs = [ "autumn", "hidden", "bitter", "misty", "silent", "empty", "dry", "dark", | |
| "summer", "icy", "delicate", "quiet", "white", "cool", "spring", "winter", | |
| "patient", "twilight", "dawn", "crimson", "wispy", "weathered", "blue", | |
| "billowing", "broken", "cold", "damp", "falling", "frosty", "green", |
This is what happens when I try to pick a language.
Note: If I didn't think it was possible to create a development environment without any of these issues (which I consider "major" for the most part), I would not have written this list.